Die-stock.



PATENTED MAY 8, 1906.

F. B. DOWNS.

DIE STOCK.

APPLIGATION FILED JAN.26, 1905.

2 SHEETS-SHEET 1,

No. 819,868.v PATBNTED MAY 8, 1906. F. B. DOWNS.

DIE STOCK.

APPLIGATION FILED 15.11.26, 1905.

` 2 SHEETS-SHEET 2.

TrETTEn sTETE's PATENT oEEicE FRED B. DOVNS, OF WARREN, OHIO.

DiE-STOCK- Specification of Letters Patent.

Patented May 8, 1906.

Application led January 2B. 1905. Serial No. 242.731.

.substantially as shown and described, and

more particularly pointed out iii the claims.

y object is to provide a die-stock'to cut either right or left hand threads by a simple adjustment of the parts and also to provide an adjustable supporting bushing or bearing for engaging the article being threaded.

I am aware that various devices have been made wherein the dies are adjustable and adapted to be set by a cainlate; but to the best of my knowledge an belief my construction providing foi" adjustment of two sets of dies by a single cam-plate is novel with me. In the accompanying drawingsFigure 1 is a face view of my improved die-stock with the cam-plate partly broken away to disclose the inner construction.

n Fig. 2 is a cross-sec` tion on line :c 9;, Fig. 1, with a pipe in position land threaded. Fig. 3 is a face view of the opposite side of the die-stock from that seen in Fig. 1 with the cam-plate for the bushing or bearing members partly broken away. Fig. 4 is an inner face view of the die-operating cani-plate; and Fig. 5 is a cross-section of the die-stock on line 'y y, Fig. 1.

The body or casing A of my improved diestock has two oppositely-disposed recessed portions or heads B and C, respectively, of varying diameter,D the larger of the two serving as a die-support and the smaller one as a bushing or bearing support to hold the diestock centrally' to its work ais said stock is rotated. Portion B has an oii't'er circular flange 2, with radially-disposed walls 3,"arranged in pairs and extending therefrom to the inner annular flange 4, forming the Wall for central opening 5 ofp body A. In the present instance I employ six threading-dies adapted to slide between radial walls 3, and said dies are divided into two sets of three dies each, I) and E, respectively, one set of which is adapted to cut right-hand threads andthe other set left-hand threads. i It is obvious that only one set of dies can be used at the same time. Therefore one set of dies is retired within casing A while the other set is at work.

The means for sliding the respective dies back and forth and for holding them rigidly in working position comprise the camlate ,F, rotatably supported upon the (outer aces of body portion B, and said platehas -a series of ribs 6 and 7, respectively, adapted to engage the individual dies of each set D and E, respectively. Ribs 6 and 7 are arranged at an angle to each other and form more or less of an obtuse angle, and said ribs are eaclhng adapted to engage in the groove or recess 8 in the upper exposed edge 9 of each die. Said ribs are mainly relied upon to withdraw each die from the work and to retire the same within casing A. Owing to the strainand pressure upon the dies when at work, it is essential that a firm backing be provided for each die, and therefore I provideunclined shoulders 9 and.10 for the respective dies, which shoulders and the outer rounded ends 11 ofv each die enaage'to force said dies inward and to positively hold them against a return movement unless plate F is rotated. Said shoulders are inclined on parallel lines with the ribs for the dies, and as both are tangentially arranged upon plate -F'it will be seen that as said plate is. rotated one set of diesis moved inward and the otherset of dies is moved outward, this occurring by reason of the oppositely-inclined 'shoulders and ribs as above described. PlateF is provided with bolts 13, which project through slots 14 in body A and has thumb-nuts 15 to secure the plate in place after it hasv once beenlset. Side bosses 16 are provided for body A, into which the usual pipe-arms 17 are screwed and wherewith the stock is rotated as usual.

An equivalent construction to that shown for operating the dies and body portion B is further provided within body ortion C for radially-disposed bushing mem ers 20, having rollers at their inner ends adapted to bear at equal points from the center upon the pipe being threaded, and thereby furnishing a ceiitral uide and support for body A as it is rotated about the pipe. Only three members 20 are provided in this instance, and said members are each adapted to slide in channels `between radial ribs 21 within portion C. A plate G, similar to plate F, is used to carry IOO IIO

the members in and out; but said plate has its tangentially-disposed ribs 22 and shoulder 23 all arranged at the same angle in respect to each member 20. Plate G also hasv suchas bolts and thumbfnuts 24, tol

means, secure the plate against movement after it has been rotated to ix the members 2O in any position.

In order that definite degrees of rotation for plateF and a redetermined movement of the dies for setting them to thread standard siaes of pi es may be obtained, I provide a spring an flange 2 of body A, and which is ad-a ted to enter any one of several openingsKpin the peri hery of lug 15 on plate F.

at I claim is- 1. In a die-stock, a casing and separate sets of radially-movable right and left thread-- ing dies therein, a single rotatable member engaged With all the dies and constructed to .move said separate sets of dies in opposite pin-latch J, mounted ,upon

directions when said member is rotated in either direction.

2. In a die-stock, a casing and separate sets of radially-movable dies therein, a rotatable plate having oppositely-inclined ribs and shoulders adapted to move the respective sets of dies in opposite directions, and means on said casing adapted to set said plate for predetermined degrees of rotation in either direction.

3. In a die-stock, the casing and radiallymovable dies mounted therein, a rotatable plate having oppositely-inolined engaging portions for lseparate dies adapted to move the same in opposite directions, and means to lock said plate upon said casing.

.In testimony whereof I sign this specifica-` tion in the presence of two Witnesses.

` y FRED B. DOWNS Witnesses:

' C. A. SELL,

' R. B. MOSER. p 

